1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 2004 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 #pragma ident "%Z%%M% %I% %E% SMI" 28 29 /* Copyright (c) 1988 AT&T */ 30 /* All Rights Reserved */ 31 32 33 #include "synonyms.h" 34 #include "file64.h" 35 #include "mtlib.h" 36 #include <stdio.h> 37 #include <stddef.h> 38 #include <values.h> 39 #include <memory.h> 40 #include <thread.h> 41 #include <synch.h> 42 #include <errno.h> 43 #include <sys/types.h> 44 #include "stdiom.h" 45 #include "mse.h" 46 47 size_t 48 fread(void *ptr, size_t size, size_t count, FILE *iop) 49 { 50 ssize_t s; 51 int c; 52 char *dptr = (char *)ptr; 53 rmutex_t *lk; 54 55 FLOCKFILE(lk, iop); 56 57 _SET_ORIENTATION_BYTE(iop); 58 59 /* is it a readable stream */ 60 if (!(iop->_flag & (_IOREAD | _IORW))) { 61 iop->_flag |= _IOERR; 62 errno = EBADF; 63 FUNLOCKFILE(lk); 64 return (0); 65 } 66 67 if (iop->_flag & _IOEOF) { 68 FUNLOCKFILE(lk); 69 return (0); 70 } 71 72 /* These checks are here to avoid the multiply */ 73 if (count == 1) 74 s = size; 75 else if (size == 1) 76 s = count; 77 else 78 s = size * count; 79 80 while (s > 0) { 81 if (iop->_cnt < s) { 82 if (iop->_cnt > 0) { 83 (void) memcpy((void*)dptr, iop->_ptr, 84 iop->_cnt); 85 dptr += iop->_cnt; 86 s -= iop->_cnt; 87 } 88 /* 89 * filbuf clobbers _cnt & _ptr, 90 * so don't waste time setting them. 91 */ 92 if ((c = __filbuf(iop)) == EOF) 93 break; 94 *dptr++ = (char)c; 95 s--; 96 } 97 if (iop->_cnt >= s) { 98 char *tmp = (char *)iop->_ptr; 99 switch (s) { 100 case 8: 101 *dptr++ = *tmp++; 102 /*FALLTHRU*/ 103 case 7: 104 *dptr++ = *tmp++; 105 /*FALLTHRU*/ 106 case 6: 107 *dptr++ = *tmp++; 108 /*FALLTHRU*/ 109 case 5: 110 *dptr++ = *tmp++; 111 /*FALLTHRU*/ 112 case 4: 113 *dptr++ = *tmp++; 114 /*FALLTHRU*/ 115 case 3: 116 *dptr++ = *tmp++; 117 /*FALLTHRU*/ 118 case 2: 119 *dptr++ = *tmp++; 120 /*FALLTHRU*/ 121 case 1: 122 *dptr++ = *tmp++; 123 break; 124 default: 125 (void) memcpy((void*)dptr, iop->_ptr, 126 (size_t)s); 127 } 128 iop->_ptr += s; 129 iop->_cnt -= s; 130 FUNLOCKFILE(lk); 131 return (count); 132 } 133 } 134 FUNLOCKFILE(lk); 135 return (size != 0 ? count - ((s + size - 1) / size) : 0); 136 } 137